A vulnerability in the SAML 2.0 single sign-on (SSO) feature of Cisco Secure Firewall ASA Software and Secure FTD Software could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, resulting in a DoS condition. This vulnerability is due to insufficient error checking when processing SAML messages. An attacker could exploit this vulnerability by sending crafted SAML messages to the SAML service. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.
Weakness
The product uses insufficiently random numbers or values in a security context that depends on unpredictable numbers.
Potential Mitigations
- Use a well-vetted algorithm that is currently considered to be strong by experts in the field, and select well-tested implementations with adequate length seeds.
- In general, if a pseudo-random number generator is not advertised as being cryptographically secure, then it is probably a statistical PRNG and should not be used in security-sensitive contexts.
- Pseudo-random number generators can produce predictable numbers if the generator is known and the seed can be guessed. A 256-bit seed is a good starting point for producing a “random enough” number.
Related Attack Patterns
- https://cwe.mitre.org/data/definitions/112.html
- https://cwe.mitre.org/data/definitions/485.html
- https://cwe.mitre.org/data/definitions/59.html